1. Field of the Invention
The present invention relates to a storage apparatus, a control method, and a control device which download and update firmware which is drive control software which records and reproduces data in accordance with update requests from a host, and particularly relates to a storage apparatus, a control method, and a control device which download new firmware from a host in an operating state of the apparatus and update old software in the apparatus side.
2. Description of the Related Arts
Conventionally, firmware which is mounted as drive control software in a controller of a magnetic disk apparatus undergoes version upgrading when countermeasures against various factors generated during operation are made after the apparatus thereof is shipped to a user, and firmware of new versions is sequentially downloaded and updated. Such update of firmware in magnetic disk apparatuses has to be performed for each one of the magnetic disk apparatuses. For example, in a disk array system which is connected to a host as a subsystem, with respect to a large number of magnetic disk apparatuses mounted in the disk array, new-version firmware is transferred and downloaded from the host to the apparatus side, and update of the firmware is executed in the apparatuses. In the conventional magnetic disk apparatus, firmware is separately stored in a flash memory which is a non-volatile memory provided in the apparatus and a magnetic disk. When the apparatus is started up, a boot code stored at a top position of the flash memory is executed, the firmware in the flash memory and the firmware in the magnetic disk medium is read, written to a buffer memory and a SRAM which are volatile memories, and executed by a CPU so as to execute recording/reproducing of data to or from the magnetic disk medium. A conventional firmware updating process for such magnetic disk apparatus is performed according to the following procedure.
However, such a conventional firmware updating method has a problem that, when an error occurs during update of the firmware with respect to the flash ROM and the magnetic disk medium and the data is destroyed, or when a process is disrupted by an error immediately after update of the flash ROM and the firmware of the magnetic disk medium cannot be updated, a diagnosis error of the flash ROM occurs when the power is turned on again next time, the firmware cannot be started up, and the apparatus becomes unusable.